KSCE Journal of Civil and Environmental Engineering Research (대한토목학회논문집)

Korean Society of Civil Engeneers (대한토목학회)
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Horizontal Wave Pressures on the Crown Wall of Rubble Mound Breakwater Under a Non-Breaking Condition: Effect of the Armour Crest Width

비쇄파조건에서 경사식방파제의 상치콘크리트에 작용하는 수평파압: 피복재 어깨폭 영향

  • 이종인 (전남대학교 공과대학 토목공학과) ;
  • 임호석 (전남대학교 해안항만실험센터) ;
  • 조지훈 (전남대학교 대학원 건축토목공학과)
  • Received : 2022.01.05
  • Accepted : 2022.03.24
  • Published : 2022.08.01
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Abstract

To design the crown wall of rubble-mound breakwaters, the horizontal wave load should be available, but determining this load remains difficult. Lee et al. proposed modification factors for Goda's formula for the horizontal wave pressures on acrown wall. The empirical formula by Lee et al. was based on a two-dimensional model test with a relatively narrow armour crest width in front of the crown wall. In this study, a series of experiments at the same facility were conducted on the horizontal wave pressures on the crown wall of a rubble-mound breakwater with a wide armour crest width. As a result, the pressures of the unprotected part of the crown wall were nearly identical to the narrow crest width. However, the pressures of the protected part tended to decrease with a change in the armour crest width. From the experimental results, the horizontal pressure modification factors of Goda's formula including the armour crest width effect are suggested here and are likely applicable to practical designs of the crown walls of rubble-mound breakwaters covered with tetrapods.

경사식방파제의 상치콘크리트 설계를 위해서는 수평파압이 산정되어야 하지만 불명확한 부분이 있다. Lee et al.은 상치콘크리트에 작용하는 수평파압 산정시 적용되고 있는 Goda 파압식의 수평파압보정계수를 제안하였다. Lee et al.의 제안식은 2차원 실험결과에 기반을 두고 있으며, 상치콘크리트 전면 피복재 어깨폭이 좁은 경우에 대한 것이다. 본 연구에서는 동일한 실험장비를 이용하여 피복재 어깨폭이 넓은 조건에 대한 수평파압 계측실험을 수행하였다. 노출부 구간의 경우에는 피복재 어깨폭의 증가에 따른 수평파압의 변화는 크지 않았으며, 보호부 구간의 경우에는 어깨폭이 증가함에 따라 수평파압이 감소하였다. 실험결과를 이용하여 피복재 어깨폭의 영향을 고려한 Goda 파압식의 파압보정계수를 제안하였다. 본 제안식은 테트라포드가 피복된 경사식방파제의 상치콘크리트 설계에 실무적으로 적용 가능할 것으로 기대된다.

Keywords

Acknowledgement

본 논문은 해양수산부 및 해양수산과학기술진흥원의 연구비 지원(과제번호: 20180323)으로 수행된 연구이며, 연구비 지원에 감사드립니다.

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